Skimmer protector with integral blow tube

ABSTRACT

A skimmer protector with integral blow tube is a hollow, substantially closed, blow-molded body of resilient resin material having a cylindrical projection on one end with external screw threads for threading into the intake pipe of a swimming pool skimmer with an open integral tube running from and through said screw threaded portion to an opening elsewhere on its blow-molded body. The cylindrical projection on the body of the device is intended and designed to be threaded into the intake pipe or other part of a pool skimmer. When connected thereto, the skimmer protector is positioned to absorb/buffer the forces exerted by the expansion of ice as it freezes within the walled regions of the skimmer. The aforesaid integral tube serves to create a sealed air space between the tube and the outer walls. This sealed air space helps to resiliently stiffen the body of the skimmer protector, allowing it to better perform its function in absorbing ice expansion pressure. In addition, this sealed integral tube can be used as a blow-out tube to assist in the removal of water from the piping connected to the skimmer.

[0001] This application claims the benefit of U.S. ProvisionalApplication No. 60/259,652, filed on Jan. 4, 2001, which provisionalapplication is incorporated by reference herein.

TECHNICAL FIELD

[0002] Our invention pertains to the general field of devices intendedfor the protection of swimming pools from freeze damage. Moreparticularly, it deals with a skimmer protector for placement in theskimmer of a swimming pool.

BACKGROUND

[0003] Winter freeze-up of swimming pools causes considerable damagefrom ice expansion, particularly in the region of the skimmer for thepool. A prior invention of a skimmer protector (U.S. Pat. No. 3,552,267)of one of the co-inventors of this application recognized the specialneed for protection within the skimmer area and provided a simple,effective, and economical means for absorbing the expansion of ice inthe skimmer to prevent damage to the skimmer. In the past, theprotection provided by this invention has been supplemented by the useof blow-out tubes to force compressed air through skimmer piping inorder to remove all water that might freeze in the winter and crack thepiping. However, there has heretofore been no device that provided bothfeatures.

SUMMARY OF THE INVENTION

[0004] Our invention is a hollow, substantially closed, blow-molded bodyof resilient resin material having a cylindrical projection on one endwith external screw threads for threading into the intake pipe of aswimming pool skimmer with an open integral tube running from andthrough said screw threaded portion to an opening elsewhere on itsblow-molded body. The cylindrical projection on the body of the deviceis intended and designed to be threaded into the intake pipe or otherpart of a pool skimmer. When connected thereto, our invention ispositioned to act as a skimmer protector and absorb/buffer the forcesexerted by the expansion of ice as it freezes within the walled regionsof the skimmer. Its function in this role is improved by the inclusionof the aforesaid integral tube, which serves to create a sealed airspace between the tube and the outer walls of our invention. This sealedair space helps to resiliently stiffen the body of our invention,allowing it to better perform its function in absorbing ice expansionpressure. In addition, this sealed integral tube can be used as ablow-out tube to assist in the removal of water from the pipingconnected to the skimmer.

DRAWINGS

[0005]FIG. 1 shows an elevational cross-sectional view of a swimmingpool skimmer with our invention installed in place.

[0006]FIG. 2 shows a cross-sectional view of a portion of the top of ourinvention with a plug positioned for insertion therein.

DETAILED DESCRIPTION

[0007] A skimmer (denoted generally by arrow 10) includes an inletpassageway 11 having a weir 12 leading to a walled chamber 14 having acover 13 and an intake pipe 15 for drawing water from the pool to thepump and filter (not shown). Skimmer 10 can have many different shapesand sizes and can open in various ways to a pool. Also, various pipescan lead from intake pipe 15 to the pool filtration equipment. Most ofthe multitude of such skimmer arrangements can be protected by ourinvention.

[0008] Our invention has a blow-molded body 16 that is hollow,substantially closed, and formed of resilient resin material. Body 16 isgenerally cylindrical or formed into cylindrical sections as illustratedand has a diameter larger than intake pipe 15 where it is adjacent tointake pipe 15. The generally cylindrical shape of body 16 is preferredfor ease of blow molding, but body 16 can have other shapes if desired.

[0009] In the preferred embodiment illustrated, a narrowed portion 16Aof body 16 is also provided so as to allow the invention to be fittedinto intake pipe 15 close to the side of walled chamber 14 withoutinterference from a skimmer basket support rim 14A. In addition,gripping means in the form of raised semi-cylindrical projections orlugs 16B are provided around the top of body 16 to afford a betterfinger grip for screwing body 16 into intake pipe 15.

[0010] A cylindrical projection with external threads depends from body16 for threading into the internal threads of intake pipe 15. Mostswimming pool skimmers have a 1.5 inch tapered pipe thread in intakepipe 15. Others have a 2 inch tapered pipe thread in intake pipe 15.Thus, both a larger set of upper threads 17 (with a 2 inch diameter) anda smaller set of lower threads 18 (with a 1.5 inch diameter) areprovided. However, different sized thread combinations can be providedas needed with the lower set of threads always, of course, being smallerthan the upper set of threads. O-rings can be used with each set ofthreads 17, 18 to assure a complete seal when seated in intake pipe 15.

[0011] An integral tube 19 runs through the center of body 16. Integraltube 19 and body 16 are coaxial with integral tube 19 forming a hollowcylindrical channel in body 16 running between a lower opening at thebase of lower threads 18 and an upper opening at the top of body 16.Integral tube 19 is adapted for use as a blow tube in clearing -pipe 15.Tube 19 can extend beyond body 16 and can also be provided with exteriorcaps and/or insertion plugs (such as plug 20) if desired to preventwater from entering pipe 15 via tube 19 when pipe 15 is not in use. Suchplugs or caps can be held in place frictionally by the use of screwthreading, by snap rings, or by other means and can be provided foreither or both ends of tube 19.

[0012] When body 16 and tube 19 are joined, our invention has a sealedair space (denoted generally by arrow 21) between the outer surface ofits body 16 and integral tube 19. This sealed air space 21 helps toresiliently stiffen the body of our invention, allowing it to betterperform its function in absorbing ice expansion pressure. Many materialsare suitable for forming body 16 and integral tube 19. However, ourpreferred materials are synthetic, thermal plastic resins, such aspolyethylene. From a manufacturing standpoint, body 16 can beadvantageously formed by blow molding and integral tube 19 viaextrusion. These two parts can then be joined/welded at their loweredges and at their upper edges to form our invention.

[0013] During the molding process, an additional cylindrical protrusionor standoff is preferably formed on the flat surfaces present at the topand bottom of body 16. The top surface of each protrusion is reamed out,leaving only the walls of the protrusion. A tube of greater length thanbody 16 is then slipped through the openings that remain from the reamedout protrusions. Each end of the tube is then swaged, joined, or weldedto the wall of the protrusion with heat and pressure so as to formintegral tube 19. This results in a slightly raised ring or ridge 22 ofplastic on the top and bottom surfaces of body 16. The raised ridge 22of the top surface will accommodate a stopper such as plug 20 to preventwater from entering through the top of integral tube 19 afterinstallation.

[0014] A second means of forming the top and bottomprotrusions/stand-offs could be employed using a large size blow-pinduring the molding process. This would create the raised walls on thetop surface of body 16 for welding with integral tube 19 without goingthrough the secondary process of reaming the protrusion. Additionally,the stand-off on the bottom surface of body 16 could be formed duringthe molding process by inserting a “dummy pin” into the mold cavity justprior to the injection of air used to give the part its shape.

[0015] The welding, joining, or swaging of body 16 with integral tube 19is done using a heated ring. This heated ring captures both the wall ofthe protrusion and the wall of the integral tube 19. The two walls ofplastic are joined by simultaneously melding and compressing them toform sealed raised, circular ridge 22 on the flat surface at both thetop and bottom of the part. The heated “welding” ring is used inconjunction with a slightly tapered lead-in. This lead-in centers theheating ring and prevents integral tube 19 from collapsing or distortingduring the “welding/joining”. The tapered lead-in is made of anon-conductive, non-stick material that allows it to be used as acentering device and partially as a swage block allowing theheating/welding process to occur primarily on the exterior of the part.

[0016] To install our invention, it is merely necessary to remove cover13 and screw body 16 into pipe 15 via the appropriately sized screwthreads provided. With body 16 threaded in place, intake pipe 15 isprotected from ice and debris and body 16 extends above intake pipe 15into the walled regions of skimmer 10 where it can be compressed byexpanding ice to protect walls 14 from ice pressure. (The resilientmaterials forming body 16 and integral tube 19, as well as the aircontained in air space 21, are readily compressed by expanding ice.) Inaddition, integral tube 19 is installed and ready to be used in clearingpipe 15 of any water that might freeze and cause damage. The flat uppersurface of body 16 can accommodate air pressure devices or blower hosesof many different sizes. These are pressed against the top surface ofbody 16 in order to blow air through integral tube 19. Following thisprocedure, a plug 20 can be inserted to cap off the top of integral tube19. After the ice season, body 16 is unscrewed and removed to ready thepool for use.

[0017] Persons wishing to practice the invention should remember thatother embodiments and variations could be adapted to particularcircumstances. Even though one point of view is necessarily chosen indescribing and defining the invention, this should not inhibit broaderor related embodiments going beyond the semantic orientation of thisapplication but falling within the spirit of the invention. For example,many sizes and configurations of our invention can be used within thespirit of the invention. Moreover, our invention can also be producedusing other techniques well known in the art such as heat sealing, spinwelding, or ultrasonic welding.

We claim:
 1. A skimmer protector for use in a swimming pool having askimmer including a walled region and an intake pipe, comprising: a. ahollow, substantially closed body of resilient material; b. one end ofsaid body having a screw threaded cylindrical projection that can bethreaded into said intake pipe; c. a hollow blow-out tube incommunication with said intake pipe extending from said intake pipethrough said cylindrical projection to an outer opening located on saidbody; and d. said body extending from said intake pipe to becompressibly disposed within said walled region.
 2. The device of claim1 wherein the outer opening is located at an end of the body oppositethe cylindrical projection.
 3. The device of claim 1 wherein asubstantially sealed air space exists between the blow-out tube and saidbody.
 4. The device of claim 1 wherein said body is generallycylindrical in shape.
 5. The device of claim 4 wherein said body has alarger diameter than said intake pipe.
 6. The device of claim 5 whereina portion of said body arranged to confront a skimmer basket support rimis narrower in diametrical relationship to said cylindrical projectionthan a portion of said body adjacent to said cylindrical projection. 7.The device of claim 1 wherein the end of said body opposite thecylindrical projection has gripping means to afford a finger grip forscrewing said body into said intake pipe.
 8. The device of claim 1further comprising a removable cap for sealing an end of said hollowblow-out tube.
 9. The device of claim 1 wherein said screw threadedcylindrical projection has portions with different diameters, therebyenabling the device to be screwed into intake pipes having suchdifferent diameters.
 10. The device of claim 1 wherein a raised rimsurrounds the outer opening.
 11. A skimmer protector with integral blowtube for use in a swimming pool having a skimmer including a walledregion and an intake pipe, comprising a hollow body of resilientmaterial having a cylindrical projection on one end with external screwthreads for threading into the intake pipe of a swimming pool skimmerwith an open integral blowout tube running from and through said screwthreaded portion to an opening located at an end of the body oppositethe cylindrical projection so as to form a substantially sealed airspace between said blow-out tube and said body.
 12. The device of claim11 wherein said body is generally cylindrical in shape and has a largerdiameter than said intake pipe.
 13. The device of claim 12 wherein aportion of said body arranged to confront a skimmer basket support rimis narrower in diametrical relationship to said cylindrical projectionthan a portion of said body adjacent to said cylindrical projection. 14.The device of claim 13 wherein an end of the body opposite thecylindrical projection has gripping means to afford a finger grip forscrewing said body into said intake pipe.
 15. The device of claim 14further comprising a removable cap for sealing an end of said hollowblow-out tube.
 16. The device of claim 15 wherein said screw threadedcylindrical projection has portions with different diameters, therebyenabling the device to be screwed into intake pipes having suchdifferent diameters.
 17. The device of claim 16 wherein a raised rimsurrounds the opening.